Automatic turn-signal controller

ABSTRACT

An automatic turn-signal control device comprising an axially displaceable threaded member which is driven for rotation by a driving cable extended from the driving shaft of the vehicle with a speed reduction, a pair of pawls either of which can exclusively engage with or disengage from the threaded member, a pair of turn-signal switches which are closed or opened in response to the engagement or disengagement of either pawl, externally operable means to urge either of the pawls from a neutral position for automatically resetting either pawl to a neutral position away from its engagement with the threaded member at the point where the threaded member has attained a predetermined axial displacement, and means for automatically resetting the disengaged threaded member to its starting point.

United States Patent 191 Yasuda [76] inventor: Kiichi Yasuda, 1-35Funakoshi-machi, Yokosuka 237, Attorney John Lezdgy et Japan [22] Filed:July 25, 1972 [57] ABSTRACT Y [2 l 1 Appl. No.: 274,984 An automaticturn-signal control device comprising an axially displaceable threadedmember which is driven for rotation by a driving cable extended from thedriv- [301 Foreign Appnnflon priority Data ing shaft of the vehicle witha speed reduction, a pair Sept. ll, i97i Japan 46/070536 of p l eitherof which can exclusively g g with or disengage from the threaded member,a pair of turn- [52] US. Cl ZOO/61.27, 74/2, 340/56 signal Switcheswhich are closed or opened in response [51] Int. Cl. t th g g or di g gt f ith p l [58] Field of Search 2( )O/6l.27, 74/2, tuna), Operablemeans to urge either of the pawls 340/56 73 from a neutral position forautomatically resetting either pawl to a neutral position away from itsengage- [56] References Cited ment with the threaded member at thepointwhere the UNITED STATES PATENTS threaded member has attained apredetermined axial 2,009,693 7/1935 Heising 340/56 displacement, andmeans for automatically resetting 1 the disengaged threaded member toits starting point.

7 Claims, 3 Drawing Figures I29 3 i l l I H l 22 g H 2 22 J L- i C I isi 24 ,VI 2

4| 37 -40 39 i) o I 38 AUTOMATIC TURN-SIGNAL CONTROLLER [451 July17,1973

Primary Examiner-Robert K. Schaefer Assistant Examiner-Gerald P. ToimPAIENIEDJIIH m F SHEET 2 [IF 3 PATENIEDJUHTIQH sum 3 ers AUTOMATICTURN-SIGNAL CONTROLLER This invention relates to an automatic controldevice which can positively and reasonably control the warning signalgeneration and termination on road vehicles, such as automobiles, motorcycles, and bicycles, when used by drivers turning intersections orchanging lanes on highways.

Ordinary automatic turn-signal control devices are so designed that aprotuberance formed on the handle shaft of a vehicle turns off thecontact of a tum-signal switch at the point where the handle shaft hascompleted a certain angular displacement. They have the followingdisadvantages: (a) In the case where a motorist turns his car to theleft or right at an intersection with the handle not turned beyond apredetermined angle, for example on a three-forked road where the roadis branched at an angle of 120, the vehicle completes its turningmovement and resumes running straightly forward before the resettingprojection on the handle shaft has been displaced to the resettingposition. Consequently, the v'ehicleruns while continuing the flashingof lamps on the particular side of the vehicle, unless the turn signalis reset by hand. This dangerously puzzles and misguides the drivers ofoncoming and following vehicles and pedestrians alike, and can be asource of traffic accidents or other troubles. (b) There is a dead pointwhere the angular displacement position of the resetting projection onthe handle shaft coincides with that of an actuating arm for thetum-signal switch. Any attempt of the driver to switch on the turnsignal at that dead point will be in vain because the projection keepsthe arm from moving to the switching position. Naturally the turn signalwill not work at the dead point. It sometimes occurs that, after theturn signal has'been switched on at an angular displacement position alittle distance past the dead point, the driver is compelled to turnback the handle slightly to steer clear of an oncoming vehicle orpedestrian. In such a case the projection often resets the arm, therebyconcluding the signalling in the midst of the turning movement andmaking it necessary for the driver to turn on the signal switch onceagain. (d) With the construction of an ordinary turn signal describedabove, it is impossible to have the signal turned off automaticallyafter it has been switched on to change the lane for the vehicle byreason of overtaking or otherwise and the vehicle has accordingly movedto the'new lane. Unless it is turned off by hand, the turn signal willcontinue to work and flash the lamps unnecessarily just in the same wayas described in (a) above.

It is an object of the present invention to provide a novel and uniqueautomatic turn-signal control device which can eliminate the foregoingdisadvantages, generate warning signals positively and easily at anytime desired, and accurately and automatically terminate the signallingupon conclusion of the turning movement of the vehicle when the angle ofturning is insufficient as well as when it is sufficient, withoutprematurely ceasing the signalling in the course of the turningmovement.

The concept of this invention may be briefly summarized as follows.Because the various disadvantages of the conventional devices areascribable to the construction whose switching action is based on theangular displacement of the handle shaft, it may be considered advisableto base the action on some other factor.

Then the idea of dependency upon time may occur to one skilled in theart. However, time is not a desirable factor in that it provesinconvenient or useless in traffic jams. The present invention succeedsin solving all of the foregoing problems by basing the switching actionon the distance that the vehicle covers for its turning motion. Moreparticularly, the invention resides in a construction comprising anaxially displaceable threaded member which is driven for rotation by adriving cable extended from the driving shaft of the vehicle with aspeed reduction, a pair of pawls either of which can exclusively engagewith or disengage from the threaded member, and a pair of tum-signalswitches which are closed or opened in response to the engagement ordisengagement of either pawl, either of said pawls being urged byexternally operable means from a neutral position into exclusiveengagement with the threaded member, either pawl being automaticallyreset to a neutral position away from its engagement with the threadedmember at the point where the threaded member has attained apredetermined axial displacement, while the disengaged threaded memberbeing automatically reset to its starting point.

The construction according to the present invention will be described inmore detail below in conjunction with the accompanying drawings showingan embodiment thereof.

BRIEF DESCRIPTION OF THE DRAWINGS i FIG. 1 is a top plan view of theturn signal control device of this invention;

FIG. 2 is a vertically sectional front elevation taken on the line 2-2of FIG. 1; and

FIG. 3 is a vertically sectional side elevation taken on the line 33 ofFIG. 1.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIGS. 1, 2 and 3,the front end portion of a driving cable is shown extended from thedriving shaft of a vehicle with a speed reduction indicated at 4 asbranched out from a speed-meter driving cable (not shown). The spindlev5 is connected to the front end portion of the driving cable to bedriven thereby. A support pin 6 rotatably supports the upper end portionof the spindle 5, and a support bar -7 which pivotally supports the mainstem of the support pin. The front and rear frames 8 and 9, tumably bearthe both ends of the support bar in place. Also shown are a pair of sideframe 10, l l, which are interconnected at the bottoms with a bottomplate 12. The bottom plate 12 is formed with a round hole in the centerin threaded cngagement with a sleeve 13 which also serves as a guideskirt for a hollow cone 17. A bottom cover 14 is in threaded connectionwith the lower end portion of the sleeve 13. Adjacent the center of thebottom cover 14 is provided a bearing 14a which supports the spindle 5.A connector 14b in threaded engagement with the bearing 14a connects aflange formed at the upper end of the driving cable to a recess at thelower end of the spindle 5. A boss I5 is axially slidable over thespindle along a key 16. On the boss 15 is securely mounted a hollow cone17, having on its outer surface a continuously spiralled thread 18 whichis sharply serrated. A tension spring 19 is secured at the lower end tothe spindle and at the upper end to the boss 15.

A pair of pawls 20 and 21 protrude inwardly from the lower end of a bellcrank 22 bifurcated from the support bar 7. Upon a rightward or leftwardinclination of the bell crank 22, either the pawl 20 or 21 provided atthe right or left, as the case may be, will exclusively engage thethread 18. From the upper center of the bell crank 22 a column 23protrudes with a cap 24 thereon. On both sides of the cap a pair oflateral slots 25, 26 are formed, and a pair of protuberances 27 formedon both sides of the column loosely fit in the slots, in such a mannerthat the cap 24 is secured to the column 23 by the protuberances with aslight allowance for circumferential displacement. A leaf spring 28 isloosely inserted in a vertical slit fonned in the center at the head ofthe cap 24. It is fixed at the base end to a bracket 29 which in turn isanchored to the rear frame 9. The spring has a bend point in the centerso that when bent rightward or leftward the spring remains bent andrefuses to be turned back to the straight position. A bifurcated arm 30holds the cap within its U-shaped bifurcation with a pivot 31 for thebifurcated arm and an oper ating lever 32 for the arm. Pressure balls 33fasten the operating lever in its neutral position. For this purpose theballs are urged forward into engagement with grooves 35 formed in theportions of the boss 34 surrounding the pivot 31. The balls allow for anangular displacement of the lever 32 when the lever is so displaced indefiance of the pressures being exerted thereby. A pair of microswitchactuating horns 36, 37 protrude from the both sides of the boss 34 forthe lever 32, and are associated with the contacts 33, 39, respectively,of a pair of microswitches 4t), 41.

When the vehicle is running straight forward the operating lever 32 isin the position indicated by solid lines, with the pair of pressureballs 33 fitted in the grooves 35 to keep the boss 34 from turning. Thebifurcated arm 30 therefore maintains the cap 24 in the upright positionagainst the biasing action of the leaf spring 28. Accordingly, the pairof pawls 20, 21 formed in the lower ends of the legs of the bell crank22 are kept away from engagement with the threaded portion 18, thusleaving the portion 18 in its starting point with the boss under thedownward urging of the spring 19. The hollow cone is normally runningidle as it-is driven, through the key 16, by the spindle 5 directlycoupled to the driving cable 4.

When it becomes necessary to light the right or left side flasher lampsin order to turn the vehicle at an intersection or change its lane on ahighway, the driver turns the operating lever 32 for an angulardisplacement in the direction where the vehicle is to turn, just in thesame manner as with a conventional turn signal. For example, if thedriver turns the lever 32 clockwise, the angular displacement of thelever tilts the bifurcated arm 30 via the pivot 31 to the right asviewed in FIG. 1. Also, the microswitch actuating born 36 on the boss 34moves the contact 38 to connect the microswitch 40, thereby allowing theside flashers (not shown) on that side of the vehicle to flash. At thesame time, the cap 24 is tilted rightward by the bifurcated arm 30,whereas the bell crank 22 is inclined leftward with the support bar 7 asthe fulcrum until the pawl 20 meshes with the threaded portion 18. Then,because the threaded portion 18 is continuously revolving, the pawl 20runs along the thread, with the result that the hollow cone l7 graduallyascends with the boss 15 in sliding contact with the spindle 5 againstthe downward urging of the spring 19. Since the threaded portion 18extends over the truncated conical surface of the hollow cone 17, theradius of engagement between the threaded portion 13 and the pawl 20increases in direct proportion of the distance that is covered by thevehicle after the switching of the turn signal. As a result, the cap 24which supports the pawl 20 through the bell crank 22 gradually returnsto the upright position in defiance of the spring 28. This motion isaccompanied by the movement of the bifurcated arm 30 to toward itsneutral position. Then the pressure balls 33 fit in the grooves 35 ofthe boss 34, and the pawl 20 is disengaged from the thread of thethreaded portion 18. Upon the disengagement of the pawl 20, the threadedportion 18 is brought back to its original point by the tension of thespring 19. In this way all the parts are reset to their initialpositions, the microswitch 40 being cut off by the return of the horn 36to its normal position. The side flashers are not automatically put off.If the operating lever 32 is turned counterclockwise for an angulardisplacement in the other direction, the microswitch 41 and the pawl 21on the other side of the controller are actuated and, by the sameprocedure above described, the flashing by the turn signal isautomatically stopped after the veicle has run a certain distance, forexample after a run of 200 meters, from the point where the turn signalwas switched on.

If either of the pawls in engagement with the threaded portion isdisengaged by manual resetting of the operating lever 31 while thevehicle is in the midst of its turning movement, the threaded portion 18at once returns by itself to its starting point. If the necessity arisesimmediately thereafter to engage either pawl with the threaded portion18 by the operating lever 32, the driver can light the side flasherlamps over the predetermined distance of travel from the point ofengagement where the threaded portion 18 is in its starting point.

As another embodiment of the present invention, it is possible toprovide the threaded portion 18 on a cylindrical drum, so that the drumcan be urged upward by the engagement of the portion with either pawluntil it pushes open the inner base portion of the bell' crank 22 todisengage the pawl from the threaded portion. The same effect may beachieved by providing the threaded portion 18 in the form of internalthreading on the inner wall of the cylindrical drum, in engagement witheither of the pawls 20, 21 which protrude outwardly, not inwardly.

The automatic resetting means for the threaded portion 18 may take theform of gravity or weight, or the tension spring may be replaced by acompression spring to obtain, naturally, the same effect.

With the construction and operation above described, the presentinvention permits automatic control of a turn signal in relation to thedistance of travel of the vehicle carrying the control device. Thus,because the signal generation is terminated without fail after a run ofthe vehicle over a predetermined dis tance, there is no possibility ofthe vehicle running with the side flasher lamps on after the vehicle hasresumed straight running following a turn. As long as the vehicle stayswithin the predetermined distance, for example due to a trafficcongestion, the signal generation is continued regardless of time. Thereis no danger of the rotational angle of the steering handle causing anyinability, premature termination, or impossibility of automatictermination, of the signal generation. Even when the signal isregeneratedimmediately after the signalling has been stopped by hand,the signalling can be resumed from the starting-point of thepredetermined distance. The control device of the present invention canthus achieve these and other advantageous effects which are neverattainable with the conventional devices.

What is claimed is:

I. An automatic turn signal control device communicating with a drivingcable extending from the driving shaft of a vehicle with a speedreduction means for actuating and then deactuating the turn signalsafter a turn comprising an axially displaceable threaded memberconnected for rotation with said driving cable and normally running idleas it is driven; a pair of pawls, each of said pawls being engageableand disengageable with said threaded member; a pair of turn signalswitch means operative in response to either of said pawls; externalmeans for urging either of said pawls from a neutral position intoengagement with said threaded member so as to indicate a turn; 'meansfor automatically resetting either of said pawls to a neutral positionaway from engagement with said threaded member at a point where saidthreaded member is at a predetermined axial displacement, and means forautomatically resetting said disengaged threaded member to its startingpoint.

2. The device of claim 1 wherein said external means for urging saidpawls from a neutral position is a manual operating lever which isangularly displaceable in the direction the vehicle is indicated asturning and returned to the neutral position after completion of theturn.

3. The device of claim 1 wherein said threaded member has on its outersurface a continuously spiralled thread which is sharply serrated.

4. The device of claim 1 wherein said pawls are formed at the lower endsof a bell crank bifurcated from a support bar.

5. The device of claim 4 wherein upon inclination of 7 said bell crankone of said pawls engages said threaded member.

6. The device of claim 1 wherein said threaded member is a truncatedhollow cone having the threaded portion extending over the outer conicalsurface. I

7. The device of claim 1 wherein said means for resetting said threadedmember is a spring means.

1. An automatic turn signal control device communicating with a drivingcable extending from the driving shaft of a vehicle with a speedreduction means for actuating and then deactuating the turn signalsafter a turn comprising an axially displaceable threaded memberconnected for rotation with said driving cable and normally running idleas it is driven; a pair of pawls, each of said pawls being engageableand disengageable with said threaded member; a pair of turn signalswitch means operative in response To either of said pawls; externalmeans for urging either of said pawls from a neutral position intoengagement with said threaded member so as to indicate a turn; means forautomatically resetting either of said pawls to a neutral position awayfrom engagement with said threaded member at a point where said threadedmember is at a predetermined axial displacement, and means forautomatically resetting said disengaged threaded member to its startingpoint.
 2. The device of claim 1 wherein said external means for urgingsaid pawls from a neutral position is a manual operating lever which isangularly displaceable in the direction the vehicle is indicated asturning and returned to the neutral position after completion of theturn.
 3. The device of claim 1 wherein said threaded member has on itsouter surface a continuously spiralled thread which is sharply serrated.4. The device of claim 1 wherein said pawls are formed at the lower endsof a bell crank bifurcated from a support bar.
 5. The device of claim 4wherein upon inclination of said bell crank one of said pawls engagessaid threaded member.
 6. The device of claim 1 wherein said threadedmember is a truncated hollow cone having the threaded portion extendingover the outer conical surface.
 7. The device of claim 1 wherein saidmeans for resetting said threaded member is a spring means.